Valve plug assembly for pressure regulator

ABSTRACT

A valve plug adapted for sealing engagement with a seat ring. The valve plug includes a cylindrical body with an annular flange having a groove. A pair of bores is disposed in the body, each bore having a first diameter, a first end, and a second end disposed within the body. Each bore is also adapted to receive a fastener to couple the valve plug to a mounting portion, and a recess is disposed at the second end of the bore, forming a stepped portion. The recess is adapted to receive at least one of a portion of a retainer or a portion of the fastener. A sealing disk is disposed within the groove of the annular flange and is one of a machined sealing disk or a molded sealing disk.

FIELD OF THE DISCLOSURE

The present disclosure generally relates to fluid control devices and,more particularly, to valve plug assembly for a fluid control device.

BACKGROUND

Fluid control devices include various categories of equipment withcontrol valves and regulators. Such control devices are adapted to becoupled within a fluid process control system such as chemical treatmentsystems, natural gas delivery systems, etc., for controlling the flow ofa fluid therethrough. Each control device includes a body defining afluid flow-path and a control member assembly for adjusting a dimensionof the flow-path. A seat ring is disposed within a throat of the valvebody.

The control member assembly typically includes a valve plug assemblyhaving a sealing disk with a sealing surface. When the outlet pressureof the valve body is high, a sealing surface of the sealing disk maysealingly engage the seat ring and close the throat. This prevents theflow of fluid through the regulator. In one example, the sealing diskmay be a machined sealing disk used with the regulator, and in anotherexample, the sealing disk may be a molded sealing disk.

More specifically, FIG. 1 depicts one known valve plug assembly 10. Inthis example, the valve plug assembly 10 is attached to a mountingmember, such as a disk holder 12 or a sleeve adapter, for example, whichis coupled to a sleeve 14. The valve plug assembly 10 includes amachined, polyurethane sealing disk 16 with a sealing surface 17. Themachined sealing disk 16 is coupled to the disk holder 12 by a retainer18. Screws 20 and washers 22 secure the retainer 18 and the sealing disk16 to the disk holder 12, for example, but other fasteners mayalternatively be used.

FIG. 2 depicts another known valve plug assembly 100. In this example,the valve plug assembly 100 is again attached to a mounting member, suchas a disk holder 112, or sleeve adapter, which is coupled to a sleeve114. The valve plug assembly 100 includes a molded nitrile rubber, suchas NBR, sealing disk 116 having a sealing surface 117. The moldedsealing disk 116 is coupled to a retainer 130 having a differentgeometric configuration than the retainer 18 of FIG. 1, for example.Screws 132 and washers 134 again secure the retainer 130 and the sealingdisk 116 to the disk holder 112, but other fasteners may again be used.In this example, a seat ring 136 is depicted, which is adapted to be incontact with the sealing surface 117 of the sealing disk 116.

As described, the machined sealing disk 16 depicted in FIG. 1 and themolded sealing disk 116 of FIG. 2 require different retainers 18, 130 beused to secure the sealing disks 16, 116, respectively, to the diskholders 12, 112, for example. In addition, while screws 20, 132 and nuts22, 134 are both used to secure the retainers 18, 130 to the diskholders 12, 112, often the retainers 18, 130 require a different numberand kind of screws 20, 132 and/or nuts 22, 134. Such variations in theretainers 18, 130 and corresponding screws 20, 132 and nuts 22, 134 usedfor each of the machined sealing disk 16 and the molded sealing disk116, respectively, makes service of such disks 16, 116 more complicated.Said another way, servicing the sealing disks 16, 116 requires a user toknow whether the valve plug assembly 10, 100 includes the machinedsealing disk 16 or the molder sealing disk 116 so that a requiredcorresponding retainer and screws and nuts are used, for example.

In addition, and as depicted in FIG. 1, an additional o-ring 24 orsimilar sealing mechanism is required to be disposed adjacent to themachined sealing disk 16 between the retainer 18 and the disk holder 12.This additional o-ring 24 used with the machined sealing disk 16 is notrequired or needed with the molded sealing disk 116 depicted in FIG. 2,for example. Thus, a user replacing or servicing the machined sealingdisk 16 would need to make sure an additional and proper o-ring 24 orsimilar sealing mechanism was also included during installation and/orafter replacing, repairing and/or servicing the sealing disk 16, forexample.

SUMMARY OF THE DISCLOSURE

One aspect of the present disclosure includes a valve plug adapted forsealing engagement with a seat ring. The valve plug comprises acylindrical body with an annular flange radially extending from the bodyand having a groove. A pair of bores is disposed one or more of on or inthe body, each bore having a first diameter, a first end adapted to bein contact with a mounting portion, and a second end disposed within thebody. In addition, each bore is adapted to receive a fastener to couplethe valve plug to the mounting portion. A recess is disposed at thesecond end of each bore, and each recess has a second diameter largerthan the first diameter of the bore to form a stepped portion at thesecond end of each bore. The recess is adapted to receive at least oneof a portion of a retainer or a portion of the fastener. A sealing diskis disposed within the groove of the annular flange. The sealing disk isone of a machined sealing disk that is machined into the groove or amolded sealing disk that is molded to the groove and has a sealingsurface adapted to engage a seating surface of the seat ring. Soconfigured, when the sealing disk is the machined sealing disk, therecess receives a portion of a retainer, and when the sealing disk isthe molded sealing disk, the recess receives a portion of the fastener.In this way, the same valve plug and one or more fasteners areinterchangeably used with both the machined sealing disk and the moldedsealing disk.

According to another aspect of the present disclosure, a fluid controldevice, comprises a valve body defining a flow path for a fluid, a seatring disposed within the flow path; and an actuator coupled to the valvebody. The actuator includes a control assembly adapted for displacementrelative to the seat ring for regulating a flow of the fluid through theflow-path. The control assembly includes a mounting portion and a valveplug coupled to the mounting portion and adapted to sealingly engage theseat ring. The valve plug comprises a cylindrical body and an annularflange radially extending from the cylindrical body, the annular flangehaving a groove. In addition, the valve plug includes a pair of boresdisposed in the cylindrical body, each bore having a first diameter, afirst end in contact with the mounting portion, and a second enddisposed within the cylindrical body. Further, each bore is adapted toreceive a fastener to couple the valve plug to the mounting portion. Arecess is disposed at the second end of each bore, and each recess has asecond diameter larger than the first diameter of the bore to form astepped portion at the second end of each bore. Further, the recess isadapted to receive at least one of a portion of a retainer or a portionof the fastener. In addition, a sealing disk is disposed within thegroove of the annular flange. The sealing disk is one of a machinedsealing disk that is machined into the groove or a molded sealing diskthat is molded to the groove and has a sealing surface adapted to engagea seating surface of the seat ring.

In further accordance with any one or more of the foregoing first andsecond aspects, the valve plug may include any one or more of thefollowing forms.

According to one aspect, the sealing disk may comprise polyurethane atleast in part, and the valve plug may comprise a metal material. Inaddition, the sealing disk may comprise the machined sealing disk, andfurther include a gasket disposed within the groove between the flangeand the machined sealing disk.

According to another aspect, the flange may include a top surfaceadapted to contact the disk holder and a bottom surface, and the groovemay extend into the bottom surface of the flange. In addition, the bodymay include a top surface and a bottom surface, the first end of eachbore at the top surface of the body, and the second end of each boredisposed within the body a distance from the bottom surface of the body.

In yet another aspect, the recess may be a screw head recess adapted toreceive a screw head of the fastener. In addition, the screw head of thefastener may be moved out of a flow path to improve stability of aregulator.

In still another aspect, the sealing disk may include the molded sealingdisk, and the fastener may then couple the valve plug to the mountingportion without a retainer. When the sealing disk is the molded sealingdisk, the molded sealing disk may comprise a nitrile material at leastin part, and the valve plug may comprise a metal material.

In another aspect, the distance between each bore in the valve plug maybe the same. Said another way, each bore in the valve plug may beequidistant from the other bore.

In addition, the when the sealing disk is the machined sealing disk, thecontrol device may further comprise a retainer in contact with the valveplug to secure the valve plug to the mounting portion. A portion of theretainer may be disposed within the recess of the valve plug, and ascrew head of the fastener may be disposed within the retainer. Further,the retainer may also include a portion in contact with the sealingsurface of the valve plug.

In yet another aspect, when the sealing disk is the machined sealingdisk, the recess may receive a portion of a retainer, and when thesealing disk is the molded sealing disk, the recess may receive aportion of the fastener, such that the same valve plug and one or morefasteners are interchangeably used with both the machined sealing diskand the molded sealing disk.

BRIEF DESCRIPTION OF THE DRAWINGS

It is believed that the disclosure will be more fully understood fromthe following description taken in conjunction with the accompanyingdrawings. Some of the drawings may have been simplified by the omissionof selected elements for the purpose of more clearly showing otherelements. Such omissions of elements in some drawings are notnecessarily indicative of the presence or absence of particular elementsin any of the example embodiments, except as may be explicitlydelineated in the corresponding written description. Also, none of thedrawings is necessarily to scale.

FIG. 1 is a cross-sectional view of a known valve plug assembly having amachined sealing disk adapted to be used with a regulator assembly;

FIG. 2 is cross-sectional view of another known valve plug assemblyhaving a molded sealing disk adapted to be used with a regulatorassembly;

FIG. 3 is a cross-sectional view of a fluid control device having avalve plug assembly according to the present disclosure;

FIG. 4 is a cross-sectional view of the valve plug assembly of FIG. 3,the valve plug assembly having a valve plug with a machined sealingdisk; and

FIG. 5 is cross-sectional view of the valve plug assembly of FIG. 3, thevalve plug assembly having a valve plug with a molded sealing disk.

DETAILED DESCRIPTION OF THE DISCLOSURE

A valve plug adapted for sealing engagement with a seat ring isdisclosed. The valve plug includes a cylindrical body and an annularflange extending from the body, the annular flange having a groove. Apair of bores is disposed in the cylindrical body, each bore having afirst end adapted to be in contact with a mounting portion, a second enddisposed within the body, and adapted to receive a fastener to couplethe valve plug to the mounting portion. A recess is disposed at thesecond end of each bore and is adapted to receive at least one of aportion of a retainer or a portion of the fastener. A sealing disk isdisposed within the groove of the annular flange, the sealing disk oneof a machined sealing disk or a molded sealing disk, the sealing diskhaving a sealing surface adapted to engage a seating surface of the seatring. When the sealing disk is a machine sealing disk, the recessreceives a portion of a retainer, and when the sealing disk is a moldedsealing disk, the recess receives a portion of the fastener, such thatthe same valve plug and one or more fasteners are interchangeably usedwith both the machined sealing disk and the molded sealing disk,requiring fewer parts for installation and service of the valve plug.

Referring now to FIG. 3, a fluid flow control device or regulatorassembly 200 including a valve plug assembly 210 of the presentdisclosure is depicted. The regulator assembly includes a valve body 212and an actuator 214. The valve body 212 defines a flow-path 216 andincludes a throat 218. In FIG. 3, the regulator assembly 200 isconfigured in a flow-up configuration. The actuator 214 includes anupper actuator casing 220, a lower actuator casing 222, and a controlmember assembly 224. The control member assembly 224 is disposed withinthe upper and lower actuator casings 220, 222 and is adapted forbi-directional displacement in response to changes in pressure acrossthe regulator assembly 200. So configured, the control member assembly224 controls the flow of fluid through the throat 218. Additionally, asis depicted, the regulator assembly 200 includes a seat ring 226(depicted in part) disposed in the throat 218 of the valve body 212.When the outlet pressure of the valve body 212 is high, a sealingsurface of the control member assembly 224 may sealingly engage the seatring 226 and close the throat 218, as described more below, to preventthe flow of fluid through the regulator 200.

The seat ring 226 depicted in FIG. 3 further includes a partiallyrounded or tapered surface 227. The rounded or tapered surface 227serves to streamline the flow of the fluid through an orifice 229. Asfluid flows through the valve body 212, it flows from the left of thevalve body 212, as depicted in FIG. 3 and up through the throat 218 viathe orifice 229 in the seat ring 226. Then, the fluid deflects off alower surface of the control member 224, and out to the right of thevalve body 212 of FIG. 3.

Generally, the control member assembly 224 is adapted to be engaged by aseating surface 230 (FIGS. 4 and 5) of the seat ring 226 when thecontrol member assembly 224 is in a closed position (not depicted),preventing the fluid from flowing through the valve body 212. Morespecifically, the control member assembly 224 further includes a tubularmember 232, a mounting subassembly 234, and the valve plug assembly 210,e.g., disk holder assembly. The tubular member 232 includes an upper end232 a and a lower end 232 b. The lower end 232 b is open andaccommodates the mounting subassembly 234. The valve plug assembly 210is coupled to the mounting subassembly 234, for example, as generallydepicted in FIG. 3.

Referring now to FIG. 4, the valve plug assembly 210 includes a valveplug 240 or a disk holder having a machined sealing disk, as explainedmore below. The valve plug 240 includes a generally cylindrical body 242having a center portion 244 and an annular flange 246 radially extendingfrom the body 242. The annular flange 246 includes a bottom portion 248,such as a bottom surface, and an annular groove 250 disposed in thebottom portion 248. At least one bore 252, and in one example, a pair ofbores 252 is disposed in the body 242 of the valve plug 240. The pair ofbores 252 includes a bore 252 disposed on either side of the centerportion 244 of the body, and each bore 252 is equidistant from the otherbore 252, as depicted in FIG. 4. The bore 252 also includes a firstdiameter D1, a first end 254 adapted to be in contact with a mountingportion 256 of the mounting assembly 234 (FIG. 3), and a second end 258disposed within the body 242. The bore 252 is adapted to receive afastener 259 to couple the valve plug 240 to the mounting portion 256,for example. In one example, the fastener 259 is a threaded fastener orthreaded screw and in another example the fastener is a nail or stud.One of ordinary skill in the art will appreciate that various otherfasteners may alternatively be used and still fall within the scope ofthe present disclosure.

The valve plug 240 further includes a recess 260 disposed at the secondend 258 of the bore 252. The recess 260 includes a second diameter D2larger than the first diameter D1 of the bore 252 to form a steppedportion 262 at the end 258 of the bore 252. In this example, the recess260 is adapted to receive a portion 264 of a retainer 266.

More specifically, the retainer 266 includes at least one bore 267 thatis axially aligned with the bore 252 of the valve plug 240. In addition,the at least one bore 267 of the retainer 266 has a diameter that issubstantially identical to the diameter D1 of the bore 252 of the valveplug 240. Further, the retainer 266 also includes at least one recess269 disposed at one end of the at least one bore 267 of the retainer266. The recess 269 has a diameter that is substantially identical tothe diameter D2 of the recess 260 of the valve plug 240. In this way,the bore 267 of the retainer 266 also receives a portion of the fastener259, and the recess 269 of the retainer 266 receives a screw head 261 ofthe fastener 259, for example. In one example, the recess 269 of theretainer 266 is a screw head recess. One of ordinary skill in the artwill appreciate that the at least one bore 267 of the retainer 266 mayinclude a pair of bores 267 or a plurality of bores 267, wherein eachbore 267 of the retainer 266 is axially aligned with each bore 252 ofthe valve plug 240, for example, and still fall within the scope of thepresent disclosure. Further, one of ordinary skill in the art will alsoappreciate that the at least one recess 269 may include a pair ofrecesses 269 disposed at the ends of the each bore 267 of a pair ofbores 267 and also still fall within the scope of the presentdisclosure.

Still referring to FIG. 4, the valve plug 240 further includes a sealingdisk 268 disposed within the groove 250 of the annular flange 248. Inthis example, the sealing disk 268 is a machined sealing disk that ismachined into the groove 250 and includes a sealing surface 270 adaptedto engage the seating surface 230 of the seat ring 226. In this example,the machined sealing disk 268 comprises polyurethane at least in part,and the valve plug 240 comprises a metal material.

In another example, the valve plug 240 may further include a gasket 272disposed in the groove 250 between the sealing disk 268 and the annularflange 246. The gasket 272 prevents high pressure and air from gettingbehind the sealing disk 268 in high pressure applications of theregulator assembly 200, which causes moderate to severe unwantedvibrations of the valve plug 240. As a result, the gasket 272significantly reduces, if not eliminates, any unwanted vibrations due tohigh pressure and/or air behind the sealing disk 268 during operation ofthe regulator assembly 200.

As further depicted in FIG. 4, the body 242 of the valve plug 240further includes a top surface 274 and a bottom surface 276. The firstend 254 of the bore 252 is disposed at the top surface 274 of the body242. The second end 258 of the bore 252 is disposed within the body 242a distance from the bottom surface 276 of the body 242.

Referring now to FIG. 5, the valve plug assembly 210 is again depicted,the valve plug assembly 210 having the valve plug 240 (or disk holder,for example), but instead of the machined sealing disk 268 (FIG. 4), amolded sealing disk 280 is included within the valve plug 240. Becausethe valve plug 240 of FIG. 5 is essentially the same as the valve plug240 of FIG. 4, parts of the valve plug 240 of FIG. 4 identical to thevalve plug 240 of FIG. 5 share the same reference numerals and aremostly explained above relative to FIG. 4, for the sake of brevity.

As depicted in FIG. 5, the valve plug 240 includes the cylindrical body242 with the center portion 244 and the annular flange 246 radiallyextending from the body 242. The annular groove 250 is disposed in thebottom portion 248 of the annular flange 246 and receives the moldedsealing disk 280. The dimensions of the valve plug 240, such as thediameter and the length of the groove 250 in the annular flange 246 ofthe body 242, fit both the machined sealing disk 268 depicted in FIG. 4and the molded sealing disk 280 of FIG. 5. This interchangeability oftypes of sealing disks 268, 280 able to be used with the valve plug 240of the present disclosure, for example, allows fewer parts to be used inservicing the valve plug 240 of the actuator assembly of FIG. 3, asexplained more below.

Still referring to FIG. 5, the bores 252 disposed in the body 242 of thevalve plug 240 include the first end 254 adapted to be in contact withthe mounting portion 256 of the mounting assembly 234 (FIG. 3), and thesecond end 258 disposed within the body 242. The bore 252 is againadapted to receive the fastener 259, as described above, to again couplethe valve plug 240 to the mounting portion 256, for example.

The recess 260 disposed at the second end 258 of the bore 252 has thesecond diameter D2 larger than the first diameter D1 of the bore 252 toform the stepped portion 262 at the second end 258 of the bore 252. Inthis example, however, the recess 260 is adapted to receive a screw head261 of the fastener 259, as depicted in FIG. 5. More specifically, inthis example, the recess 260 is a screw head recess that receives thescrew head 261 of the fastener 259, such that the screw head 261 ismoved out of the flow path 216 (FIG. 3), improving the stability of theregulator assembly 200. So configured, in this example, no retainer 266is required to secure the valve plug 240 to the mounting portion 256,for example, as required for the machined sealing disk 268 of FIG. 4.Said another way, the fastener 260 and screw head 261, the screw head261 fitting directly into the recess 260 of the valve plug 240, couplethe valve plug 240 having the molded sealing disk 280 to the mountingportion 256 without any need for a retainer.

While two bores 252 are depicted in FIGS. 4 and 5, one of ordinary skillin the art will appreciate that only one bore 252 and recess 260 or morethan two bores 252 and associated recesses 260 may alternatively be usedand still fall within the scope of the present disclosure. Likewise,each bore 252 and recess 260 will include corresponding fasteners 260and screw heads 261.

One of ordinary skill in the art will also appreciate that both themachined sealing disk 268 and the molded sealing disk 280 include agenerally ring-shaped disk made of resilient material, such aspolyurethane or nitrile rubber, as described above relative to themachined sealing disk 268 and the molded sealing disk 280, respectively.In one example, the machined sealing disk 268 may be fixed or bonded tothe valve plug 240 with an adhesive.

One of ordinary skill in the art will further appreciate the variousadvantages of the valve plug 240 of the present disclosure. For example,using fewer parts than conventional designs, the new valve plug 240described above allows both the machined sealing disk 268 and the moldedsealing disk 280 to use the same valve plug 240 and fasteners 259. As aresult, installation and service of the valve plug 240 (and fluidcontrol device) is more efficient and easier to manage than conventionalvalve plugs, one of which was required for machined sealing disks andanother, different valve plug and associated parts were required formolded sealing disks. In addition, both the retainer 266 and valve plug240 include the recesses 260, 261 for receiving a screw head of thefastener 259, for example. So configured, whether the sealing disk isthe machined sealing disk 268 or the molded sealing disk 280, bothrecesses 260, 261 move the screw head of each fastener 259 out of theflow path 216 (FIG. 3) to improve stability of the regulator.

In light of the foregoing, the description of the present disclosureshould be understood as merely providing examples of the presentinvention and, thus, variations that do not depart from the gist of theinvention are intended to be within the scope of the invention.

Throughout this specification, plural instances may implementcomponents, operations, or structures described as a single instance.Although individual operations of one or more methods are illustratedand described as separate operations, one or more of the individualoperations may be performed concurrently, and nothing requires that theoperations be performed in the order illustrated. Structures andfunctionality presented as separate components in example configurationsmay be implemented as a combined structure or component. Similarly,structures and functionality presented as a single component may beimplemented as separate components. These and other variations,modifications, additions, and improvements fall within the scope of thesubject matter herein.

As used herein any reference to “one example” or “an example” means thata particular element, feature, structure, or characteristic described inconnection with the embodiment is included in at least one embodiment.The appearances of the phrase “in one example” in various places in thespecification are not necessarily all referring to the same example.

Some examples may be described using the expression “coupled” and“connected” along with their derivatives. For example, some examples maybe described using the term “coupled” to indicate that two or moreelements are in direct physical or electrical contact. The term“coupled,” however, may also mean that two or more elements are not indirect contact with each other, but yet still cooperate or interact witheach other. The examples are not limited in this context.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “has,” “having” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a process,method, article, or apparatus that comprises a list of elements is notnecessarily limited to only those elements but may include otherelements not expressly listed or inherent to such process, method,article, or apparatus. Further, unless expressly stated to the contrary,“or” refers to an inclusive or and not to an exclusive or. For example,a condition A or B is satisfied by any one of the following: A is true(or present) and B is false (or not present), A is false (or notpresent) and B is true (or present), and both A and B are true (orpresent).

In addition, use of the “a” or “an” are employed to describe elementsand components of the embodiments herein. This is done merely forconvenience and to give a general sense of the description. Thisdescription, and the claims that follow, should be read to include oneor at least one and the singular also includes the plural unless it isobvious that it is meant otherwise.

This detailed description is to be construed as examples and does notdescribe every possible embodiment, as describing every possibleembodiment would be impractical, if not impossible. One could implementnumerous alternate embodiments, using either current technology ortechnology developed after the filing date of this application.

While various embodiments have been described herein, it is understoodthat the appended claims are not intended to be limited thereto, and mayinclude variations that are still within the literal or equivalent scopeof the claims.

1. A valve plug adapted for sealing engagement with a seat ring, thevalve plug comprising: a cylindrical body and an annular flange radiallyextending from the body, the annular flange having a groove; a pair ofbores disposed in the body, each bore having a first diameter, a firstend adapted to be in contact with a mounting portion, and a second enddisposed within the body, each bore adapted to receive a fastener tocouple the valve plug to the mounting portion; a recess disposed at thesecond end of each bore, each recess having a second diameter largerthan the first diameter of the bore to form a stepped portion at thesecond end of each bore, the recess adapted to receive at least one of aportion of a retainer or a portion of the fastener; and a sealing diskdisposed within the groove of the annular flange, the sealing disk oneof a machined sealing disk machined into the groove or a molded sealingdisk molded to the groove, the sealing disk having a sealing surfaceadapted to engage a seating surface of the seat ring, wherein, when thesealing disk is the machined sealing disk, the recess receives a portionof a retainer, and when the sealing disk is the molded sealing disk, therecess receives a portion of the fastener, such that the same valve plugand one or more fasteners are interchangeably used with both themachined sealing disk and the molded sealing disk.
 2. The valve plug ofclaim 1, wherein the machined sealing disk comprises polyurethane atleast in part, and the valve plug comprises a metal material.
 3. Thevalve plug of claim 1, the sealing disk comprising the machined sealingdisk, and further comprising a gasket within the groove between theannular flange and the machined sealing disk.
 4. The valve plug of claim1, wherein the flange includes a top surface adapted to contact themounting portion and a bottom surface, the groove extending into thebottom surface of the flange.
 5. The valve plug of claim 1, wherein thebody includes a top surface and a bottom surface, the first end of eachbore at the top surface of the body, and the second end of the each boredisposed within the body a distance from the bottom surface of the body.6. The valve plug of claim 1, wherein the recess is a screw head recessadapted to receive a screw head of the fastener, such that the screwhead of the fastener is moved out of a flow path to improve stability ofa regulator.
 7. The valve plug of claim 1, the sealing disk comprisingthe molded sealing disk, and the fastener couples the valve plug to themounting portion without any retainer.
 8. The valve plug of claim 1,wherein the sealing disk is the molded sealing disk, the molded sealingdisk comprises a nitrile material at least in part, and the valve plugcomprises a metal material.
 9. The valve plug of claim 1, wherein adistance between each bore is the same.
 10. A fluid control device,comprising: a valve body defining a flow path for a fluid; a seat ringdisposed within the flow path; and an actuator coupled to the valve bodyincluding a control assembly adapted for displacement relative to theseat ring for regulating a flow of the fluid through the flow-path, thecontrol assembly including a mounting portion and a valve plug coupledto the mounting portion and adapted to sealingly engage the seat ring,the valve plug comprising: a cylindrical body and an annular flangeradially extending from the cylindrical body, the annular flange havinga groove; a pair of bores disposed in the cylindrical body, each borehaving a first diameter, a first end in contact with the mountingportion, and a second end disposed within the cylindrical body, eachbore adapted to receive a fastener to couple the valve plug to themounting portion; a recess disposed at the second end of each bore, eachrecess having a second diameter larger than the first diameter of thebore to form a stepped portion at the second end of each bore, therecess adapted to receive at least one of a portion of a retainer or aportion of the fastener; and a sealing disk disposed within the grooveof the annular flange, the sealing disk one of a machined sealing diskmachined into the groove or a molded sealing disk molded to the groove,the sealing disk having a sealing surface adapted to engage a seatingsurface of the seat ring.
 11. The control device of claim 10, whereinthe machined sealing disk comprises a polyurethane material at least inpart, the molded sealing disk comprises a nitrile material at least inpart, and the valve plug comprises a metal material.
 12. The controldevice of claim 10, wherein the sealing disk comprises the machinedsealing disk, and the groove further comprises a gasket disposed withina portion of the groove between the annular flange and the machinedsealing disk.
 13. The control device of claim 10, wherein the annularflange includes a top surface adapted to contact a mounting member and abottom surface, the groove extending into the bottom surface of theannular flange.
 14. The control device of claim 10, wherein the bodyincludes a top surface and a bottom surface, the first end of each boredisposed at the top surface of the body, and the second end of the eachbore disposed within the body a distance from the bottom surface of thebody.
 15. The control device of claim 10, wherein the recess is a screwhead recess adapted to receive a screw head of the fastener.
 16. Thecontrol device of claim 10, wherein the sealing disk is the moldedsealing disk, and the fastener couples the valve plug to the mountingportion without a retainer, a screw head of the fastener being disposedwithin the recess to secure the valve plug to the mounting portion. 17.The control device of claim 10, wherein the sealing disk is the machinedsealing member, and the control device further comprises a retainer incontact with the valve plug to secure the valve plug to the mountingportion, a portion of the retainer disposed within the recess of thevalve plug, and a screw head of the fastener disposed within theretainer.
 18. The control device of claim 17, the retainer furtherincluding a portion in contact with the sealing surface of the valveplug.
 19. The control device of claim 10, wherein a distance betweeneach bore is the same.
 20. The control device of claim 10, wherein, whenthe sealing disk is the machined sealing disk, the recess receives aportion of a retainer, and when the sealing disk is the molded sealingdisk, the recess receives a portion of the fastener, such that the samevalve plug and one or more fasteners are interchangeably used with boththe machined sealing disk and the molded sealing disk.